Howard Hughes was one of the
driving forces behind the design of the Lockheed Constellation commercial transport.
During WWII, the USAAF purchased 22 early model Constellations which were designated
as C-69s. At the end of the war, the USAAF decided to standardize on the Douglas C-54
as its four-engined transport of choice, and promptly declared most of the C-69s as
surplus. Production of the basic design was turned over to the civil market, which
lead to the famous Constellation series of airliners.

The C-121A was the military variation of commercial Model 749 Constellation. Between
1948 and 1955 the USAF ordered 150 C-121As for use as cargo/passenger carriers, executive
transports, and airborne early warning aircraft. As a troop carrier, they could carry a
maximum of 44 passengers.

Fifty-five percent of the Super Constellations built by Lockheed were
delivered to the U.S. Navy and Air Force. A majority of the aircraft were
used for electronic reconnaissance and airborne early warning. In the mid-1960s,
the Air Force sent the first EC-121 "Warning Star"
to Southeast Asia to maintain radar surveillance over North Vietnam
and then later to warn of MiG attacks and alert American pilots who were straying
over Chinese territory.

Most C-121As were later converted into the VC-121A VIP transport configuration
for use by top brass officials such as Generals MacArthur and Eisenhower. The lone
VC-121E Constellation (#53-7885) was named "Columbine III" and was used throughout
the Eisenhower Administration as Air Force One.